Exhibit 99.30 MBNA MASTER CREDIT CARD TRUST II SERIES 1997-M KEY PERFORMANCE FACTORS April 30, 1999 Expected B Maturity 10/15/02 Blended Coupon 5.1459% Excess Protection Level 3 Month Average 5.97% April, 1999 5.14% March, 1999 6.73% February, 1999 6.04% Cash Yield 17.83% Investor Charge Offs 5.23% Base Rate 7.46% Over 35 Day Delinquency 4.87% Seller's Interest 10.40% Total Payment Rate 14.17% Total Principal Balance $42,469,994,217.25 Investor Participation Amount $750,000,000.00 Seller Participation Amount $4,418,074,698.76